1. Field of the Invention
The present invention relates to USB (Universal Serial Bus) connectors and more particularly, to a female USB connector, which has a set of first metal terminals and a set of second metal terminals respectively mounted in an electrically insulative base member and an electrically insulative tongue plate to avoid signal transmission interference. The electrically insulative base member and the electrically insulative tongue plate are fastened together by means of a hook joint, simplifying installation.
2. Description of the Related Art
Following fast development of modern electronic technology, advanced consumer electronic products have been continuously created and are intensively used in our daily living for different applications. Nowadays, people use a portable notebook to substitute for a deck computer. These advanced electronic products may use a transmission cable for transmitting photos, files, programs and other data. For the transmission of data, data transmission speed is quite important. Nowadays, USB (Universal Serial Bus) interfaces are most commonly used in consumer electronic products for the advantage of hog plug function.
USB 1.1 was currently used to power our mice, scanners, printers, MP3 and many other peripherals. USB2.0 is a currently used standard that operates at 480 Mbps, about 40× times faster than USB 1.1 which currently works at just 12 Mbps. However, USB2.0 is simply suitable for powering peripheral apparatus that consume less power (such as card reader, printer, memory stick, network phone and network camera). A new generation of USB3.0 helps the users to transfer data at 10× speed compared to USB2.0. It facilitates users to download data up to 4.8 Gbits/sec (Super-Speed mode), making users much comfortable transferring the data for high-end devices such as HD videos and high resolution pictures. Typical USB3.0 based applications are removable hard drives, flash drives, high-end video and imaging devices, HDTV displays, high-resolution printer/scanner, etc. USB3.0 is compatible to USB2.0. Further, it supports full duplex, providing for an increase in power output from 100 mA to 900 mA. A USB 3.0 connector is noticeably different to its USB 2.0 counterpart. By means of extra contacts, a USB3.0 connector allows data to be sent and received at the same time.
FIG. 9 illustrates a USB2.0 female connector according to the prior art. According to this design, the USB2.0 female connector comprises an electrically insulative base member A that has defined therein a plurality of terminal slots A1, a plurality of metal terminals B respectively positioned in the terminal slots A1 in the electrically insulative base member A, and a metal shielding shell C that surrounds the electrically insulative base member A. Each metal terminal B has a rear bonding portion B1 extended out of the electrically insulative base member A for bonding to an external circuit board, and a front contact portion B2 suspending inside the electrically insulative base member A for the contact of one corresponding metal terminal of the matching male USB connector.
Based on the design of the aforesaid USB2.0 female connector, extra metal terminals may be installed in the electrically insulative base member A to constitute a USB3.0 female connector. However, due to limited internal space, it is difficult to install a row of extra metal terminals in the electrically insulative base member A. Further, when a big number of metal terminals are installed in the electrically insulative base member A, signal transmission interference may occur, lowering the signal transmission quality or resulting in a transmission interruption.